Electrified Downhill bike

[johnrobholmes]

Here is my last build. Running an HV110 , Magura 5k throttle, 12s 10ah hobby city lipos, and some larger hub motor.

About 25mph, good wheelies, and handles great. I get about 18 miles of full throttle thrashing on a charge, enough to go to town and back and have 20% left.


Pack fits in the frame right above the cranks. Next project is to weld up a battery box and some mount tabs on the frame.

[zeropointbug]

Hey johnrob, nice build man. I have been doing some research on parts and equipment for an electric bike, as well as an electric motorcycle.

If I can get that 12x A123 cell deal for a somewhat bulk order, then it will be golden! 58cents / Wh for $65 for 12 cells.

If I go ahead on the electric motorcycle, I plan to use somwhere between 25hp and up to even 70hp. I still need to do more research on how much hp it compares to gasoline for bikes. In cars, it's about 2:1 ratio, of electric:gasoline performance per hp, like you need 1/2 as much hp to have the same acceleration as gasoline, but not topspeed.

Keep it up.

[jlustig83]

Man that is a sweet build. What kind of hub motor is that? I was thinking about getting the new 600 watt BMC hub motor. Can a bmc motor be hooked up to an hv 110 ?

[johnrobholmes]

The HV110 will work on any hub motor. This one is carried by ebikekit.com, but they are no longer importing rears.


The BMC motor looks pretty nice, although I think they are overpriced for what they are. Since I haven't taken them apart maybe I am missing something about the construction though. I have use the slightly smaller Bafang motors with great luck.

[johnrobholmes]

I got a motor mounted up on the LeToy for a RC style power system. I will be using a Castle ICE HV160 for now while an EV controller I am developing is in design phase.

Power system:
Astro 3010-6
12s 10ah or 20ah zippy lipo
ICE hv160
Magura throttle
Home made DSP for throttle to PWM converter
Hyperion 12s charger or raw DC power supply for charging
Battery Medic devices for balancing


I also laced up a matching rear 17" motorcycle wheel for it, I think it looks boss and I will be keeping it this way. A shot with 26" tires is in this thread for comparison.

All I need to do is tidy up the wiring, make a battery rack, and get chain tensioners and chain lines dialed in. And a rear brake would be handy. After I broke the last hub motor I sold the parts to a buddy. I tend to break every hub motor I come across. so this is the next shot.

[jlustig83]

Power system:
Astro 3010-6
12s 10ah or 20ah zippy lipo
ICE hv160
Magura throttle
Home made DSP for throttle to PWM converter
Hyperion 12s charger or raw DC power supply for charging
Battery Medic devices for balancing


I would REALLY like to see a video of you riding a wheely on that going about 30 mph. What kind of HP is that putting out.